Key result
IV lipopolysaccharide increases sympathetic activity and inflammation but fails to alter heartbeat-evoked potentials versus placebo.
Why the study?
Whether acute inflammation affects interoceptive processing and how this relates to sickness behavior remains unknown.
Does experimental inflammation induced by intravenous LPS alter cardiac interoceptive processing and autonomic nervous system functioning in healthy females?
RCT (n=52)
Does experimental inflammation induced by intravenous LPS alter cardiac interoceptive processing and autonomic nervous system functioning in healthy females?
Experimental acute inflammation alters autonomic nervous system activity but leaves heartbeat-evoked potentials unresponsive, suggesting a complex interaction between inflammation and cardiac interoceptive processing.
Highlights potential dissociation in inflammatory effects on autonomic and interoceptive pathways; leaves open clinical relevance in cardiovascular disease.
Interoception, or the perception of internal somatic states, is crucial for signaling the individual to take care of the body when needed. It enables behavioral adaptations to sickness states, which further impact autonomic nervous system (ANS) activity. Whether acute inflammation affects interoceptive processing and how this relates to sickness behavior remains unknown. Therefore, we investigated interoceptive processing in participants undergoing experimental endotoxemia. In neuroimaging research, heartbeat-evoked potentials (HEP) - defined as event-related potentials time-locked to electrocardiogram (ECG) R-waves during electroencephalogram (EEG) recordings - have emerged as a promising metric for cardiac interoceptive processing. We analyzed the effects of intravenous administration of lipopolysaccharide (LPS; 0.4 ng/kg) or placebo, on HEP amplitudes and ANS functioning in healthy, female participants (n = 52) during 8 min resting-state EEG and ECG recordings before and 2 h after injections. Our results showed increased cortisol and cytokine levels in the LPS group, along with increased sympathetic and decreased parasympathetic activity 2 h after injections compared to the placebo group. Placebo-injected participants exhibited lower post injection-baseline differences in HEP amplitudes in an early timeframe (255-455 ms), indicating lower HEPs 2 h after administrations. Moreover, post-injection HEP amplitudes differed between groups, suggesting that while participants in the placebo group showed altered HEP amplitudes after injection, HEPs remained unresponsive to LPS administration. These findings are discussed in the context of predictive processing, expectation violation and attention direction to external and interoceptive cues. Future research should further investigate the role of LPS dose and explore behavioral measures of interoception under experimental inflammation.
No takes yet. Share an insight, caveat, or question.
Flasbeck et al. (2025) conducted an RCT in Healthy (n=52). Lipopolysaccharide (LPS) vs. Placebo was evaluated on Heartbeat-evoked potentials (HEP) amplitudes and autonomic nervous system functioning. Intravenous lipopolysaccharide (0.4 ng/kg) increased sympathetic activity and inflammation, while heartbeat-evoked potentials remained unresponsive compared to placebo at 2 hours.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: